NFPA 85 Boiler and Combustion Systems Hazard Code

The “NFPA 85 Boiler and Combustion Systems Hazard Code” standard, developed by the National Fire Protection Association (NFPA), contributes to the prevention of explosions and implosion by increasing the operational safety of boilers larger than 12,5 metric million British thermal units, powder fuel systems and heat recovery steam generators.

Boiler hazards not only affect operational performance, they can also cause explosions and endanger the lives of occupants and maintenance personnel. This standard provides anyone involved with large boiler installations and powder fuel systems with the information they need for fire safety compliance, from design and installation to inspection. This standard provides up-to-date requirements for the entire range of equipment.

Essentially, NFPA 85 is a compilation of six standards:

• NFPA 8501 Standard for single-burner boiler operation
• NFPA 8502 Standard for preventing furnace explosions/collapses in multiple-burner boilers
• NFPA 8503 Powder fuel systems standard
• NFPA 8504 Standard for atmospheric fluidized bed boiler operation
• NFPA 8505 Stoker operation standard
• NFPA 8506 Standard for heat recovery steam generator systems

NFPA 85 applies to:

• Single-burner boilers, multiple-burner boilers, stokers, and atmospheric fluidized bed boilers with a fuel input rate of 3,7 MW (12,5 million Btu/hr) or greater
• Powder fuel systems at any heat input rate
• Fired or unfired steam generators used to recover heat from combustion turbines [heat recovery steam generators and other combustion turbine exhaust systems at any heat input rate

This standard covers design, installation, operation, maintenance and training. It also covers the strength of the structure, operation and maintenance procedures, combustion and draft control equipment, safety interlocks, alarms, triggers and other related controls necessary for safe equipment operation. However, it does not cover process heaters used in chemical and petroleum production where steam generation is dependent on the operation of a processing system.

This standard covers single burner boilers burning the following fuels:

• Fuel gas as defined in this standard
• Other gas with similar calorific value and properties to natural gas
• Fuel oil defined in this standard
• Fuel gas and fuel oil burned simultaneously for fuel transfer
• Fuel gas and fuel oil burned simultaneously and continuously

For the purposes of this standard, code means a standard that is a comprehensive compilation of provisions covering a broad subject area or that is suitable for adoption into law independently of other codes and standards.

From the point of view of production, design and engineering, the owner or his representative must, in cooperation with the manufacturer, ensure that the unit does not lack the apparatus necessary for its operation in terms of pressure parts, fuel burning equipment, air and fuel metering, ignition and maintenance of a stable flame.

All fuel systems must include provisions to prevent foreign matter from interfering with the fuel supply. An evaluation is performed to determine the optimum integration of manual and automatic safety features.

The boiler, heat recovery steam generator, combustion turbine exhaust system or powder fuel system shall not be released for operation until the installation and check of the necessary safety precautions and instrumentation system have been successfully completed. The party responsible for the erection and installation of the equipment shall ensure that all associated apparatus is installed and connected in accordance with the system design.

The owner or his/her representative, the engineering consultant, the equipment manufacturer, and the operating company shall prohibit operation until the safety measures have been tested to function properly as a system. If temporary interlocks and instrumentation are required to meet these requirements, such temporary systems shall be reviewed by the purchaser, the engineering consultant, the equipment manufacturer, and the operating company, and agreement shall be reached on the ability of the system to protect equipment and personnel prior to start-up. All temporary changes shall be documented and permanent solutions shall be implemented prior to commercial operation.

The interlocking system and protective devices are tested jointly by the organization responsible for the system design and the persons who operate and maintain such system and devices. After installation but before initial operation, coordinated testing of all systems is performed. Documentation of the plant equipment, system, and maintenance activities is updated to reflect changes in the status of the equipment and operating procedures.

Among the numerous testing, measurement, analysis and evaluation studies that our organization has carried out for businesses in various sectors, it also provides testing services defined in the "NFPA 85 Boiler and combustion systems hazard code" standard with its trained and expert staff and advanced technological equipment.